27/07/2012

UK - Mylan v. Yeda

In this action the Claimant (“Mylan”) sought revocation of European Patent (UK) No. 0 762 888 (“the Patent”) and a declaration of non-infringement. The First Defendant (“Yeda”) and the Second Defendant (“Teva”) were respectively the proprietor of, and the exclusive licensee under, the Patent. The Patent relates to a material known as copolymer-1, a polymer composed of amino acids alanine, glutamic acid, lysine and tyrosine in a particular ratio. The claims protect Copolymer 1 in a specified molecular weight range, and use of this for the treatment of multiple sclerosis (“MS”). Teva sells a product which it claims is protected by the Patent under the trade mark Copaxone (non-proprietary name glatiramer acetate) for the treatment of relapsing-remitting MS.

The action raised a large number of issues: whether the claims are entitled to the first claimed priority date; whether the Patent is invalid for obviousness over the prior art; whether the Patent is invalid for obviousness as making no technical contribution, but rather being an arbitrary selection from known copolymer-1 material; whether the Patent is invalid for insufficiency because the claims are ambiguous; whether the Patent is invalid for insufficiency on classical grounds; whether the Patent is invalid for insufficiency because it makes no technical contribution; whether the Patent is invalid for added matter; and whether the sale of Mylan’s glatiramer acetate product would infringe any of the claims of the Patent.

In respect of these issues it was held: none of claims 2-3 and 5-12 is entitled to priority from the Priority Document; none of the claimed inventions is obvious in the light of the prior art, Teitelbaum 1971, Bornstein 1987 or Johnson 1994; the product claims are not obvious as being an arbitrary selection; the Patent is not insufficient in any of the ways alleged; none of the claims is invalid for added matter; and; the proposed glatiramer acetate product would infringe the Patent.

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Two particular issues on construction were the subject of heavy expert evidence and took up a large part of the judgment. Both were important for determining whether the Patent was impermissibly ambiguous, or whether it was merely difficult to construe ("fuzzy", in the language adopted by the judge): first, was whether the skilled team would consider that the word “approximately” was intended to cater for variations in both amino acid analysis and the synthesis of copolymer-1. Arnold J held that the skilled team would conclude that the claim was one that had a fuzzy boundary. It is therefore not possible to say precisely where that boundary lies. This did not mean however, that the claim was ambiguous. Secondly, the Patent used the expression “average molecular weight”, without explaining what it meant. The judge thought a skilled reader would be surprised by this omission and stated that he came close to concluding that the Patent is ambiguous, but in the end concluded that the skilled team would interpret the Patent as using “average molecular weight” to mean Mp (the molecular weight corresponding to the peak in a chromatogram of the polymer weight distribution.)

Other interesting points raised by the decision are that in cases where obviousness is alleged on Agrevo/Triazoles [1996] EPOR 171 grounds that there is an arbitrary selection with no technical contribution, the evidential burden could shift to the patentee where it is inherently unlikely that the claimed invention solves the technical problem or the opponent adduces evidence which casts doubt on this. However, the judge held that a patent which does make the invention plausible cannot be shown to be obvious by post-dated evidence. He also decided that the fundamental principle is that whether a claimed invention is obvious or not should be judged as at the priority or application date and that post-dated evidence may only be relied on to confirm that the disclosure in the patent either does or does not make it plausible that the invention solves the technical problem.